Nathan Renkas
New Member
I have been growing in a homemade aero/NFT 4" PVC pipe set up under x2 1000W for close to 5 years with very good success. Past cycles have yielded right around 2 pounds of high quality product. I use 2" net cups from start to finish with no media at all. My recent cycles, however, have been very sub par and I am concerned as to what is going wrong. My suspicions stemmed from low Mg/Ca levels. First of all I use RO water and my nute tank was running a little cool over the winter (60F), which I corrected with a tank heater up to about 75F. The pH was started at 5.2 and left to climb to 5.8, though I've learned that the lower pH can inhibit Mg uptake, thus I've started at 5.8 and allow it to climb to 6.4 before adjusting. Nutrient res also has an air stone to oxygenate. I'm using Botanicare Pro Bloom, Cal-Mag plus at 5mL/gal, Liquid Karma, Aquashield all at recommended rates on bottle. I also use 1/2tsp of unsulfured molasses per 10 gallons, superthrive at 1/4 tsp per 10 gals, as well as a high P-K from week 4 to flush. Grow tent is kept around 72-75F day and around 62-64F nights. Humidity has been around 30% during the day which I was wondering if that was too low and not allowing stomates to open for optimal metabolism. I also have CO2 enrichment which raises ppm to 1500-1800 for approximately 15 minutes each hour of the light cycle, then it falls back to normal 600ppm for the remaining 45 minutes of each hour.
As it stands, I have just started week 4 of flowering. Overall, the plants look yellow and hungry. Lower leaves are yellow and curling up probably from Mg deficiency. I've tried to lower EC (1.6-2.0) to remove excessive salt build-up, but that seemed to make problems worse. I am now running around 3.0 EC and it appears as if the tops are looking healthier, though the plants overall are very sub standard. Should I be running higher ECs with organic nutrients? Should I be running higher or lower than recommended ECs in a media-less system? I typically don't leach or flush during flowering until the last week. When I have flushed in the past it always leaves the plants looking hungry.
I know growing high quality product is an art form and I thought for a while I was getting pretty good at it. Now, however, I feel as though I've lost all confidence in my growing. I've never had any major problems like this in this system before, and everything I've tried thus far has not seemed to fix the issue. I have read so much conflicting information as to proper culture in a media-less grow. Some say very low EC is best, though I've also heard others go as high as 5-6EC for a similar system! I am very confused and desperate to correct these issues, if not for this cycle, then certainly for the next one. Any information regarding EC, pH, nutrient rates, temperature, etc. would be greatly appreciated. I will post pics tonight as the plants are in dark period now.
Thank you for your time!!
As it stands, I have just started week 4 of flowering. Overall, the plants look yellow and hungry. Lower leaves are yellow and curling up probably from Mg deficiency. I've tried to lower EC (1.6-2.0) to remove excessive salt build-up, but that seemed to make problems worse. I am now running around 3.0 EC and it appears as if the tops are looking healthier, though the plants overall are very sub standard. Should I be running higher ECs with organic nutrients? Should I be running higher or lower than recommended ECs in a media-less system? I typically don't leach or flush during flowering until the last week. When I have flushed in the past it always leaves the plants looking hungry.
I know growing high quality product is an art form and I thought for a while I was getting pretty good at it. Now, however, I feel as though I've lost all confidence in my growing. I've never had any major problems like this in this system before, and everything I've tried thus far has not seemed to fix the issue. I have read so much conflicting information as to proper culture in a media-less grow. Some say very low EC is best, though I've also heard others go as high as 5-6EC for a similar system! I am very confused and desperate to correct these issues, if not for this cycle, then certainly for the next one. Any information regarding EC, pH, nutrient rates, temperature, etc. would be greatly appreciated. I will post pics tonight as the plants are in dark period now.
Thank you for your time!!